According to Public Health England, 422,000 sexually transmitted infections (STIs) are diagnosed each year in the UK. Unfortunately, the actual number of people who contract an STI could be much higher, as there are some infections, such as chlamydia, which can exist in the body without symptoms.

Because of this, it’s important to get tested regularly if you are sexually active, including every time you have sexual contact with a new partner. If you’re planning to start a family at some point in your future, it’s even more imperative that you get tested, as some STIs can impact your fertility and can even be passed onto your baby. It’s a common misconception that the impact of STIs on fertility is a female problem – that’s just not true. There are a range of STIs that affect male fertility, impacting the quality of sperm, and even cause long term damage to the reproductive system.

The positive is that most STIs have a cure, especially if caught early. In addition, those that can’t be cured can usually be managed. With that in mind, let’s take a look at seven STIs that can affect fertility in men.

1. Chlamydia

Chlamydia is the most common curable STI and, as we mentioned earlier, most people who get chlamydia do not show symptoms. If left untreated, chlamydia can lead to a considerable decline in the motility and quality of sperm, which makes conception much more difficult.

Chlamydia can be passed to newborn babies and cause inclusion conjunctivitis when they have been delivered through a vaginal birth by a mother who has the infection. Therefore, it’s important to make sure men are tested prior to attempting conception in case the infection is passed to their partner.

2. Gonorrhea

Gonorrhea is another STI which, in most cases, shows no symptoms. Both chlamydia and gonorrhea can cause epididymitis, which is an inflammation of the tube at the back of the testicles which stores and transports sperm. Most cases of epididymitis can be treated with antibiotics, and last around six weeks; however, severe cases, or cases that are left untreated, can lead to infertility.

Gonorrhea can also be passed to newborn babies through vaginal delivery. It can cause gonococcal conjunctivitis, which can lead to blindness.

3. Syphilis

Although syphilis may seem like a problem of the past, there were still over 7,500 diagnoses of the infection in the UK in 2018. Syphilis symptoms are often mild and can go unnoticed, but the infection can last for years or decades if left untreated, and can cause serious health complications.

In terms of fertility, syphilis can cause epididymitis and erectile dysfunction. If passed on to a female partner, who then becomes pregnant, there is a chance of miscarriage and also passing the infection onto the newborn baby, which can be fatal.

4. Genital Herpes

There is a lot of stigma around genital herpes, which may be why it is not discussed as frequently as chlamydia of gonorrhea; however, it is just as serious. Unlike the two aforementioned infections, genital herpes has no cure. Symptoms (commonly blisters around the genitals) can appear and clear up by themselves, but the virus will remain in the body and may cause blisters to outbreak at any time.

There is currently little research into the effects of genital herpes on male fertility; however, one study has found that the infection can result in a low sperm count. Genital herpes can, however, be easily passed from partner to partner, and can be passed from mother to baby with serious consequences (although it is rare).

5. HIV

Human Immunodeficiency Virus (HIV) is passed from person to person through blood or body fluid transmission and can cause Acquired Immunodeficiency Syndrome (AIDs). There is no cure for HIV, but treatment can control the virus, affording those with HIV the possibility to live long and healthy lives.

As HIV breaks down the body’s immune system over time, this can lead to a higher possibility of contracting another STD which could cause fertility problems. There is also evidence that HIV can cause loss of germ cells (the cells in the body that develop into sperm) in the testes, as well as hypogonadism and low testosterone.

Although it is well known that a mother can transfer HIV to her unborn child, there is little research available to determine whether an HIV-positive father and HIV-negative mother can give birth to an HIV-positive child.

6. Hepatitis

Hepatitis is the term used to describe an inflammation of the liver, and is split into several types: A, B, C, D, E, alcoholic, and autoimmune. Hepatitis B is the most common type to be linked with sexual transmission.

According to a study in the Fertility and Sterility journal, infertility is 1.59 times higher in patients with HBV infection than in those without. This could be due to lower sperm count or mobility due to infection.

Most adult bodies are able to fight off Hepatitis B and fully recover within a couple of months. Children infected with the virus, however, are likely to develop a long-term infection which can lead to liver cirrhosis and liver cancer. According to Public Health England, Around 3,000 babies in the UK are born to women who have hepatitis B infection, and around 9 in 10 exposed babies will develop a chronic (long-lasting) infection.

7. Mycoplasma Genitalium

A lesser-known STI, Mycoplasma Genitalium (Mgen) is a bacteria that was only discovered in 1981, but this doesn’t mean that it is not as serious as other STIs. Mgen doesn’t always have symptoms but can manifest as a watery discharge from the penis, and a burning sensation when urinating.

These symptoms can be confused with a urinary tract infection (UTI), but in fact Mgen has strong links with urethritis. Urethritis can be accompanied by epididymitis, which, as we mentioned earlier, causes inflammation of the tube that carries sperm.